<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>
<!--引入vue-->
<script src="https://cdn.jsdelivr.net/npm/vue"></script>
<div id="app">
  <!--  1.直接拼接:语法过于繁琐-->
  <h2>{{firstName}} {{lastName}}</h2>
  <!--  2.通过定义methods-->
  <h2>{{getFullName()}}</h2>
  <h2>{{getFullName()}}</h2>
  <h2>{{getFullName()}}</h2>
  <!--  3.通过computed-->
  <h2>{{fullName}}</h2>
  <h2>{{fullName}}</h2>
  <h2>{{fullName}}</h2>
</div>
<script>
  const app = new Vue({
    el: "#app",
    data:{
      message:"Hello zk I am Vue !",
      firstName:'Lebron',
      lastName:'James'
    },
    methods:{
      getFullName() {
        console.log('getFullName');
        return this.firstName+" "+this.lastName
      }
    },
    computed:{
      fullName() {
        console.log('fullName')
        return this.firstName+' '+this.lastName
      }
    }
  })
</script>
</body>
</html>
